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Four years of high school and a steady dose of reality television have made Americans pretty adept at spotting liars. Everyone seems to know at least one person who compulsively flip flops — who twists the truth either for their own gain or, more maliciously, for someone else’s destruction. We call these people, of course, pathological liars.

Psychiatry is a little less cavalier about the pathological part. Pathologies are conditions or disorders that are innate to somebody’s health. Multiple sclerosis is a pathology. Cancer is a pathology. But the latest edition of the Diagnostic and Statistical Manual (DSM), psychiatry’s holy book, doesn’t list lying as its own pathology, sometimes called pseudologia fantastica. Like sociopathy, psychopathy, and other forms of social deviance, the closest the DSM comes to including pathological lying is antisocial personality disorder. And pathological lying is only a possible symptom of that larger diagnosis. So can we even say it’s real?

Why Lie?

Even if it’s not in the DSM, pathological lying is in the literature. In 2005, a group of psychiatrists published a report that tried to untangle some of the disorder’s misconceptions. For one, there are several entries in the DSM that dance around pathological lying, but never hit it on the nose. Malingering, for example, is when a person exaggerates his physical or psychological symptoms, usually to avoid certain work or criminal prosecution. Or there’s factitious disorder, in which a person intentionally falsifies the condition altogether, usually for similar gain. And antisocial personality disorder suggests habitual lying is a symptom of detachment, lack of emotion, and coldness, but the lying still isn’t necessary for a diagnosis.

“Although pathological lying was defined in the scientific literature over 100 years ago,” the researchers wrote, “it has remained poorly researched and its significance to the practice of psychiatry largely unclear.”

Dr. Howard Forman, medical director of the Addiction Consultation Service at Montefiore Medical Center, likes to paint lying as a behavior that falls on a spectrum. Ultimately, doctors need black-and-white diagnoses to progress with their patients — either people need medication or they don’t — but the characterization of a person’s illness is never so binary, he says. Lying is a complex phenomenon that sometimes turns to habit. The crucial part is understanding why someone feels compelled to do it.

“I think that if there is one central — almost universal — motivating factor, it is the avoidance of shame,” Forman told Medical Daily. Sometimes that shame involves deficiency in certain skills, like balancing a check book or reading a partner’s emotions. So, to compensate for our inadequacies, we may conceal the truth out of a desire to self-protect.

But lying has its obvious dark sides. Easy fibs may be harmless at first, but they can have an accumulating effect that gets us too comfortable with dishonesty, to the point where we sacrifice others’ well-being for our own gain. One day we’re lying about eating all the mint chocolate chip ice cream, and the next we’re cooking the books to pocket millions.

Often, to prevent these slides from ever happening, psychiatrists want to know who, exactly, is lying. If they can understand where the lying starts, the thinking goes, they can better understand it and define it. Here, too, we run into problems.

While some data exist that point to nervous-system dysfunction in 40 percent of compulsive liars, and other research implicates deficiencies in intelligence or home-life stability as the probable causes, Forman argues these claims are mostly specious.

“I think the underbelly of that is that many of our youth who are growing up in disadvantaged situations are also growing up in environments where the relationship with police and law enforcement is less than ideal,” he said. This lack of authority then translates into dishonesty, which may get read as a pathological trait rather than a reactionary or ideological one. “I do have concerns that in some of our diagnoses, especially our diagnoses like antisocial personality disorder, which is to some extent defined by problems with the law, that individuals from lower socioeconomic groups may be getting labeled really unfairly.”

Pathological lying doesn’t crop up out of nowhere like a tumor. Somewhere along the line, and then for multiple years thereafter, it gets learned.

Shades Of Gray

The focus Forman pushes for is conditioning kids not to lie. When a child takes an extra cookie before dinner and tries to hide it when she gets caught, it’s up to the parent to discipline her. If she doesn’t, Forman claims, that’s one more piece of evidence telling the child’s brain that lying works. Eradicating those thoughts early is one way to make sure pathological liars never come to be.

With that in mind, occasional lying is still necessary. It’s a social tool that keeps the peace, in the same way asking someone “Could you pass the salt?” lets us get what we want without having to demand it. The trick is coming to terms with our own behavior, so we can be self-aware enough to know if the lying is justified because it harms no one.

“The lies that are motivated by helping out your fellow people and helping them have a better day, have a more fulfilling day, a more fulfilling life — those are not harming people,” Forman said. “The real harm is coming from the lies that are motivated by people’s own self-interest.”